compiler-rt/lib/dfsan/scripts/build-libc-list.py

   1 #!/usr/bin/env python3
   2 # ===- lib/dfsan/scripts/build-libc-list.py ---------------------------------===#
   3 #
   4 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 # See https://llvm.org/LICENSE.txt for license information.
   6 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 #
   8 # ===------------------------------------------------------------------------===#
   9 # The purpose of this script is to identify every function symbol in a set of
  10 # libraries (in this case, libc and libgcc) so that they can be marked as
  11 # uninstrumented, thus allowing the instrumentation pass to treat calls to those
  12 # functions correctly.
  13
  14 # Typical usage will list runtime libraries which are not instrumented by dfsan.
  15 # This would include libc, and compiler builtins.
  16 #
  17 # ./build-libc-list.py \
  18 #    --lib-file=/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 \
  19 #    --lib-file=/lib/x86_64-linux-gnu/libanl.so.1 \
  20 #    --lib-file=/lib/x86_64-linux-gnu/libBrokenLocale.so.1 \
  21 #    --lib-file=/lib/x86_64-linux-gnu/libcidn.so.1 \
  22 #    --lib-file=/lib/x86_64-linux-gnu/libcrypt.so.1 \
  23 #    --lib-file=/lib/x86_64-linux-gnu/libc.so.6 \
  24 #    --lib-file=/lib/x86_64-linux-gnu/libdl.so.2 \
  25 #    --lib-file=/lib/x86_64-linux-gnu/libm.so.6 \
  26 #    --lib-file=/lib/x86_64-linux-gnu/libnsl.so.1 \
  27 #    --lib-file=/lib/x86_64-linux-gnu/libpthread.so.0 \
  28 #    --lib-file=/lib/x86_64-linux-gnu/libresolv.so.2 \
  29 #    --lib-file=/lib/x86_64-linux-gnu/librt.so.1 \
  30 #    --lib-file=/lib/x86_64-linux-gnu/libthread_db.so.1 \
  31 #    --lib-file=/lib/x86_64-linux-gnu/libutil.so.1 \
  32 #    --lib-file=/usr/lib/x86_64-linux-gnu/libc_nonshared.a \
  33 #    --lib-file=/usr/lib/x86_64-linux-gnu/libpthread_nonshared.a \
  34 #    --lib-file=/lib/x86_64-linux-gnu/libgcc_s.so.1 \
  35 #    --lib-file=/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc.a \
  36 #    --error-missing-lib
  37
  38 import os
  39 import subprocess
  40 import sys
  41 from optparse import OptionParser
  42
  43
  44 def defined_function_list(lib):
  45     """Get non-local function symbols from lib."""
  46     functions = []
  47     readelf_proc = subprocess.Popen(
  48         ["readelf", "-s", "-W", lib], stdout=subprocess.PIPE
  49     )
  50     readelf = readelf_proc.communicate()[0].decode().split("\n")
  51     if readelf_proc.returncode != 0:
  52         raise subprocess.CalledProcessError(readelf_proc.returncode, "readelf")
  53     for line in readelf:
  54         if (
  55             (line[31:35] == "FUNC" or line[31:36] == "IFUNC")
  56             and line[39:44] != "LOCAL"
  57             and line[55:58] != "UND"
  58         ):
  59             function_name = line[59:].split("@")[0]
  60             functions.append(function_name)
  61     return functions
  62
  63
  64 p = OptionParser()
  65
  66 p.add_option(
  67     "--lib-file",
  68     action="append",
  69     metavar="PATH",
  70     help="Specific library files to add.",
  71     default=[],
  72 )
  73
  74 p.add_option(
  75     "--error-missing-lib",
  76     action="store_true",
  77     help="Make this script exit with an error code if any library is missing.",
  78     dest="error_missing_lib",
  79     default=False,
  80 )
  81
  82 (options, args) = p.parse_args()
  83
  84 libs = options.lib_file
  85 if not libs:
  86     print("No libraries provided.", file=sys.stderr)
  87     exit(1)
  88
  89 missing_lib = False
  90 functions = []
  91 for l in libs:
  92     if os.path.exists(l):
  93         functions += defined_function_list(l)
  94     else:
  95         missing_lib = True
  96         print("warning: library %s not found" % l, file=sys.stderr)
  97
  98 if options.error_missing_lib and missing_lib:
  99     print("Exiting with failure code due to missing library.", file=sys.stderr)
 100     exit(1)
 101
 102 for f in sorted(set(functions)):
 103     print("fun:%s=uninstrumented" % f)